package org.nowcoder.huawei.other;

import java.io.BufferedReader;
import java.io.InputStreamReader;


/**
 * HJ10: 字符个数统计
 */
public class HJ10 {
    public static void hj10() throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String line = br.readLine();
        boolean[] flag = new boolean[128]; //局部数组和局部对象，会进行初始化
        int count = 0;
        for (int i = 0; i < line.length(); i++) {
            if (!flag[line.charAt(i)]) {
                count++;
                flag[line.charAt(i)] = true;
            }
        }
        System.out.println(count);
    }
}
